Malicious PDF — malware analysis report

Static analysis result for SHA-256 807673b6886f0949…

MALICIOUS

PDF

92.5 KB Created: 2021-06-24 21:12:28 +03:00 Authoring application: wkhtmltopdf 0.12.5 (via Qt 4.8.7) First seen: 2021-10-11
MD5: a573d4af71852d2096f40b1cb8d24e6f SHA-1: b75149770a317a07676d0972daedb19db51ce854 SHA-256: 807673b6886f0949bd2eeb701def2e508a83bde014716265602995daddb117a4
156 Risk Score

Malware Insights

MITRE ATT&CK
T1566.001 Spearphishing Attachment

This PDF file was flagged as malicious by ClamAV and an ML classifier. It contains numerous links to external websites, many of which appear to be compromised WordPress installations used for hosting malicious files. The document body, though heavily obfuscated, contains references to software updates, suggesting a lure to trick users into downloading the malicious PDF. The presence of multiple compromised CMS upload links indicates a link farm strategy to distribute malware.

Machine Learning

  • Nyx PDF Classifier malicious score 0.9996

Heuristics 6

  • ClamAV: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0 critical CLAMAV_DETECTION
    ClamAV detected this file as malware: Pdf.Phishing.Trojan-d2568dad23a94d95-d2568dad23a94d95-10044375-0
  • PDF link farm points to compromised-WordPress upload storage medium PDF_COMPROMISED_CMS_UPLOAD_LINK_FARM
    PDF contains multiple clickable links, across many distinct hosts, whose targets are random-slug files parked in the upload directories of vulnerable WordPress form plugins (FormCraft, Super Forms). This is the hallmark of the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains hosted on compromised sites. The PDF itself carries no exploit — the risk is the linked destinations.
  • Small PDF is a non-clustered link farm on disposable hosting medium PDF_SEO_DISPOSABLE_LINK_FARM
    Small PDF contains many clickable external PDF links spread thin across many distinct hosts (no single dominant host), corroborated by a utm_term SEO-redirector link and/or links parked on free/disposable content hosts. This is the 'free document/template' SEO phishing PDF family, which ranks for search queries and routes users into payload/redirect chains, rather than a normal document citation pattern. The PDF itself carries no exploit — the risk is the linked destinations.
  • External URI info PDF_URI
    PDF contains an external URL action
  • Object number defined twice with different bodies info PDF_DUPLICATE_OBJ_BODY_INCREMENTAL
    The same indirect object (N G) is defined more than once with different body bytes. First-wins and last-wins readers will resolve different content, which is a parser-confusion shape used by targeted PDFs. Body-only differences are common in benign incremental updates, so severity is raised only when the duplicate carries active content.
  • Embedded URL info EMBEDDED_URL
    One or more URLs were extracted from the document. The URL itself is not a detection — see the per-URL labels for which channel (macro, JS, link annotation, document body, ...) reached each URL.
    URL https://crewmak.ru/uplcv?utm_term=net+framework+4.0+v+30319+windows+7+64+bit PDF link annotation
    • https://drahmetbostanci.com/wp-content/plugins/formcraft/file-upload/server/content/files/160a87ed75083e---18376846827.pdfIn PDF document text
    • http://www.medical-psychology.gr/wp-content/plugins/formcraft/file-upload/server/content/files/1609e73b15c69f---fuxet.pdfIn PDF document text
    • https://laihouston.com/wp-content/plugins/super-forms/uploads/php/files/b20efd7cc91de6a8e3052015eb53f6e3/vabodogizabazilo.pdfIn PDF document text
    • https://nada70.org/userfiles/file/93478375160.pdfIn PDF document text
    • http://bahtiyardishekimi.com/fckfiles/file/lakefevu.pdfIn PDF document text
    • https://www.sidertest.it/wp-content/plugins/formcraft/file-upload/server/content/files/160a85aafb2661---64562155918.pdfIn PDF document text
    • https://vico-inmobiliaria.com/ckfinder/userfiles/files/43973463867.pdfIn PDF document text
    • https://sgotomotiv.org/upload/files/60746460252.pdfIn PDF document text
    • https://bowenpainter.com/wp-content/plugins/formcraft/file-upload/server/content/files/1609a7190c6a9d---xoxikugimafasase.pdfIn PDF document text
    • http://okmarin.ru/userfiles/file/xagazovidanumajowerefo.pdfIn PDF document text
    • https://baobihungphu.com/media/ftp/file/gatiremedukatebegukot.pdfIn PDF document text
    • https://alenakovalchuk.ru/wp-content/plugins/super-forms/uploads/php/files/53b456d0658a10c2be6573517d0ee7ec/97149446802.pdfIn PDF document text
    • http://tuzvedo.hu/elemek/file/52334714323.pdfIn PDF document text
    • https://www.emma-solutions.de/wp-content/plugins/formcraft/file-upload/server/content/files/160994ac6beee3---47925861780.pdfIn PDF document text
    • http://www.ascendercorp.com/In PDF document text
    • http://www.ascendercorp.com/typedesigners.htmlIn PDF document text
    • http://www.w3.org/1999/02/22-rdf-syntax-ns#In PDF document text
    • http://purl.org/dc/elements/1.1/In PDF document text
    • http://ns.adobe.com/pdf/1.3/In PDF document text
    • http://ns.adobe.com/xap/1.0/In PDF document text
    • http://ns.adobe.com/xap/1.0/mm/In PDF document text
    • http://ns.adobe.com/xap/1.0/rights/In PDF document text
    • http://dejavu.sourceforge.netIn PDF document text
    • http://dejavu.sourceforge.net/wiki/index.php/LicenseIn PDF document text
    • http://scripts.sil.org/OFLIn PDF document text

Extracted artifacts 4

Files carved from inside the sample during analysis.

FilenameKindSourceSize
stream_005_off00013dd7.bin decompressed-pdf-stream PDF FlateDecoded stream at offset 0x13DD7 22360 bytes
SHA-256: 09c0f175de6108aaa547a40563caba54c30320cac1eb750415d4e9638efdf0c1
font_00_sfnt_off0000f394.bin pdf-font-stream PDF embedded font (sfnt) at offset 0xF394 3992 bytes
SHA-256: 745dfe31fc327dc597ba7dd5bdbd5b3fc233bdd8417ebfa9c3e1d7ec52263581
font_01_sfnt_off00010195.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x10195 6216 bytes
SHA-256: a1b186097e654f25950926691481777923386cd4262890a422ed62d846692746
font_02_sfnt_off000116d1.bin pdf-font-stream PDF embedded font (sfnt) at offset 0x116D1 11608 bytes
SHA-256: 9eab7b7c25ef840d78f20692a127356c1cd5f085eafc25f51d6b5146dc346de8